Question: Simplify the following expression: $p = \dfrac{x}{8} - \dfrac{x}{10}$
Answer: In order to subtract expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $8$ and $10$ $\lcm(8, 10) = 40$ $ p = \dfrac{5}{5} \cdot \dfrac{x}{8} - \dfrac{4}{4} \cdot \dfrac{x}{10} $ $p = \dfrac{5x}{40} - \dfrac{4x}{40}$ $p = \dfrac{5x -4x}{40}$ $p = \dfrac{x}{40}$